1. Field of the Invention
The present invention relates to a device for traversing optical pickup of a disc drive, and more particularly, to a device for traversing optical pickup of a disc drive capable of smoothly transferring an optical pickup unit engaged with a lead screw along a guide shaft.
2. Description of the Conventional Art
Generally, a disc drive is an apparatus for reproducing information recorded in a disc such as a compact disc (CD), a digital versatile disc (DVD), etc. or recording information in a disc. In the disc drive, when a tray where a disc is mounted is loaded into the drive, a drive unit rotates the disc and an optical pickup unit is moved in a radius direction of the disc by an optical pickup transfer device thereby to reproduce/record information stored in the disc.
FIG. 1 is a plane view showing a device for traversing optical pickup of a disc drive in accordance with the conventional art.
As shown, the conventional a device for traversing optical pickup of a disc drive comprises: a first guide shaft 11 formed at one side of an upper surface of a deck 1; and a second guide shaft 12 formed at another side of the upper surface of the deck 1 and parallel to the first guide shaft 11 with a certain distance.
A first guide portion 15 and a second guide portion 16 are respectively formed at one side and another side of the optical pickup unit 13 so as to movably couple the optical pickup unit 13 where an optical pickup 14 is mounted to the first guide shaft 11 and the second guide shaft 12.
An insertion hole 15a for inserting the first guide shaft 11 is formed at the first guide portion 15, and an insertion hole 16a for inserting the second guide shaft 12 is formed at the second guide portion 16.
A lead screw 17 is rotatably installed at the upper surface of the deck 1 to be parallel to the first guide shaft 11.
A feed guide 18 having teeth 18a is fixed to the first guide portion 15 to be elastically coupled to the lead screw 17.
A driven gear 19 is rotatably installed at the end of the lead screw 17.
As shown in FIGS. 2 and 3, the feed guide 18 is provided with a spring 20, and the teeth 18a of the feed guide 18 are elastically coupled to the lead screw 17 by the spring 20.
A connection gear 20 is rotatably installed at the upper surface of the deck 1 to be engaged with the driven gear 19, a driving gear 21 is rotatably installed at the upper surface of the deck 1 to be engaged with the connection gear 20, and a driving motor 22 is connected to the driving gear 21.
In the conventional device for traversing optical pickup of disc drive, when the driving motor 22 rotates the driving gear 21, the driving gear 21 rotates the connection gear 20 again. The connection gear 20 rotates the driven gear 19 thus to rotate the lead screw 17. Herein, since the teeth 18a of the feed guide 18 are engaged with the lead screw 17, the optical pickup unit 13 is moved in a radius direction of the disc. At this time, the optical pickup 14 of the optical pickup unit 13 records a signal on a signal recording surface of the disc or reproduces the recorded signal by reading.
However, in the device for traversing optical pickup of a disc drive, a coupling force between the lead screw 18 and the teeth 18a are determined by an elastic force of the spring 20. According to this, in case that the elastic force of the spring 20 is set to be much less than a reference value, the teeth 18a are loosely engaged with the lead screw 18 or are not engaged thereto thereby not to smoothly transfer the optical pickup unit 13. Also, the teeth 18a of the feed guide 18 may be detached from the lead screw 17 by an external impact generated at the time of falling or carrying a product.
Additionally, in case that the elastic force of the spring 20 is set to be much more than a preset value in order to prevent said problem, the teeth 18a are too adhered to the lead screw 17 thereby not to smoothly transfer the optical pickup unit 13.